Re: Time to create index

"hpuxrac" <johnbhurley_at_sbcglobal.net> wrote in message news:1118937182.424922.184190_at_f14g2000cwb.googlegroups.com...
> amerar_at_iwc.net wrote:
>> Hi,
>>
>> Is there a way, based on the number of records in a table, to figure
>> out an estimate on how long it would take to create an index?
>>
>> This table has about 4 million rows, and the index creation time took
>> almost 20 minutes.
>>
>> Since we have a lot of large tables, I'd be curious if I can figure out
>> how long it would take to create the index.......
>>
>> Thanks,
>>
>> Arthur
>
> There is no "one size fits all" answer for this kind of question. It
> will vary greatly by what kind of disk system you have, how many
> processors, etc.
>
> But mostly it will vary by what table you are indexing, the number and
> types of columns, whether they are unique or not, etc.
>
> Did you increase the SORT memory size before running the create index?
> Did you use UNRECOVERABLE?
>
> These can help a lot ( see asktom.oracle.com on stuff like that ).
>

If you have multiple processors, building the index with the PARALLEL option can drastically improve performance ... Received on Thu Jun 16 2005 - 12:53:07 CDT